Late incidence of SARS-CoV-2 infection in a highly-endemic remote rural village. A prospective population-based cohort study

Abstract

Data on SARS-CoV-2 transmission in rural communities is scarce or non-existent. A previous cross-sectional study in middle-aged and older adults enrolled in the Atahualpa Project Cohort demonstrated that 45% of participants had SARS-CoV-2 antibodies, 77% of whom were symptomatic. Here, we assessed the incidence of SARS-CoV-2 infection in the abovementioned rural population. One month after baseline testing, 362 of 370 initially seronegative individuals were re-tested to assess incidence of seroconversion and associated risk factors. Twenty-eight of them (7.7%) became seropositive. The overall incidence rate ratio was 7.4 per 100 person months of potential virus exposure (95% C.I.: 4.7-10.2). Six seroconverted individuals (21.4%) developed SARS-CoV-2-related symptomatology. The only covariate significantly associated with seroconversion was the use of an open latrine. Predictive margins showed that these individuals were 2.5 times more likely to be infected (95% C.I.: 1.03-6.1) than those using a flushing toilet. Therefore, along one month, approximately 8% of seronegative individuals became infected, even after almost half of the population was already seropositive. Nevertheless, a smaller proportion of incident cases were symptomatic (21% versus 77% of the earlier cases), and no deaths were recorded. Whether this decreased clinical expression resulted from a lower viral load in new infections cannot be determined. Increased seroconversion in individuals using latrines is consistent with a contributory role of fecal-oral transmission, although we cannot rule out the possibility that latrines are acting as a proxy for poverty or other unknown interacting variables.

Hand grip strength before and after SARS‐CoV‐2 infection in community‐dwelling older adults

“…As such, we may have missed cases of HGS decline among middle-aged adults with SARS-CoV-2 infection. In addition, although the lateral flow-based antibody test we used is reported to have high diagnostic reliability, we cannot exclude the possibility of some degree of misclassification due to false positive or false negative results, 16,17 or the improbable scenario of cross-reactions with other viruses that are endemic in the region. 46 In summary, this longitudinal study cohort demonstrated in a select cohort an independent detrimental association between SARS-CoV-2 and HGS worsening, which reached significance among individuals with older rather than more recent infections.…”

Body Composition in Community-Dwelling Older Adults Before and After SARS-CoV-2 Infection: A Longitudinal Prospective Study in a Rural Village Struck by the Pandemic

“…Several cross-sectional and longitudinal epidemiological studies on SARS-CoV-2 infection have been conducted in this village. [15][16][17][18][19] As previously reported, Atahualpa's residents are homogeneous regarding race/ethnicity (Amerindian ancestry), socio-economic status (most men belong to the blue collar class and work as artisan carpenters, and most women are homemakers), and dietary habits (the diet is ancestrally rich in oily fish, vegetables, fruits, and carbohydrates but poor in other types of meat and dairy products). People get food mostly from the fish market and small grocery stores where highly processed foods are rarely found.…”

Cognitive decline among individuals with history of mild symptomatic SARS‐CoV‐2 infection: A longitudinal prospective study nested to a population cohort

“…Since its inception the adult population of Atahualpa has undergone tests for assessing cognitive performance, cerebrovascular diseases, epilepsy, sleep disorders and other conditions of interest [18][19][20][21]. Atahualpa was severely struck by the SARS-CoV-2 pandemic, as evidenced by a mortality rate of 21.6 per 1000 population during March-April 2020 [22], a seroprevalence of 45% among survivors [23] and an incidence rate ratio of 7.4 per 100 person-months of potential virus exposure [24]. Taking the unique opportunity of the well-established Atahualpa Project cohort, the present longitudinal prospective study aimed to assess the occurrence of cognitive decline 6 months after an episode of mild symptomatic SARS-CoV-2 infection.…”